1. Field of the Invention
The present invention relates to hoppers for storing and dispensing bulk material. More particularly the present invention relates to a space saving hopper in which the storage capacity of the hopper is essentially equal to the volume of space taken by the structure of the hopper. From another aspect, the invention relates to a hopper in which the storage capability of the hopper is variable.
2. Prior Art
Webster's New Collegiate Dictionary, copyrighted 1975, defines a "hopper" as a funnel shaped receptacle for delivering material. In practice, a hopper is more often, a modified funnel shape receptacle which is used for storing and dispensing bulk material.
Present day hoppers are used for storing and dispensing a great variety of materials and products. The products stored are usually in bulk and/or in a jumbled state. The range of products that are found to be stored in hoppers is extremely great, ranging from animal food to human food, to stone, gravel and/or sand, to containers and many other products.
The modified funnel structure of a hopper is most often very large with a wide top and sloping sides, the sides converging to a relatively narrow or confined dispensing port. The purpose of the sloped sides is to permit gravity to move the product or material stored in the hopper, to a common place in the hopper, from where the material stored may be conveniently dispensed. In some hoppers the material stored in the chamber of the hopper is dispensed out a dispensing port located in the bottom of the hopper. In other hoppers, the material is dispensed out a dispensing port located somewhat above the bottom of the chamber of the hopper. In this case, a conveyor is often used to move some of the material stored in the chamber to the dispensing port.
A major disadvantage of the modified funnel-like structure hopper is the waste of space beneath the sloped sides of the hopper. This waste of space is an economic disadvantage in production operations where space is at a premium and is expensive.
This great loss of space is amplified when the hopper is located high above the working floor because of the bottom delivery of the modified funnel structure. In an attempt to reduce this great loss of space, the delivery or dispensing port of the hopper was elevated to a location above the bottom of the chamber and a conveyor assembly was positioned and used inside the chamber to transport the product stored in the chamber to the elevated dispensing port. The funnel shape of the hopper was essentially retained in order to bring the product stored in the hopper to a particular point or area in the bottom of the chamber so that cleated belts of an internal conveyer could capture and move, even the last of the product in the chamber to the dispensing port.
The disadvantage here is that the part of the conveyor belt that is subject to the greatest wear and has the greatest potential for breakage is inside the chamber of the hopper and any breakdown of the conveyor used to move the product stored in the hopper to the elevated dispensing port results in down time for the hopper.